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Chapter 53: Building Multidimensional Cubes in Analysis Services with MDX
53
Creating User Hierarchies
To start a new hierarchy, drag an attribute to an empty spot of the pane. Add new levels by
dragging attributes onto an existing hierarchy. Remember to rename each hierarchy with a
user friendly title.The browser view is a good place to get a feel for how the user experiences the hierarchies
as created. Right-click the dimension name in the Solution Explorer, and choose Process
to update the server with the latest dimension defi nition. Then switch to the Browser tab
of the dimension designer, choose the hierarchy to view in the toolbar, and explore the
hierarchy in the pane. If the latest changes do not appear in the Browser tab, press the
Reconnect button in the toolbar. Notice names, values, and ordering associated with each
hierarchy, and adjust as needed. Note the differing icons to distinguish between user and
attribute hierarchies while browsing.Dimension Clean-Up
Not every attribute of a dimension needs to be included in the cube and not every included
attribute needs to be shown to the user. Following are a few guidelines:■ (^) Delete attributes that are not useful to users.
■ (^) Display attributes only in the hierarchy where applicable, such as individual
days of the year. For these cases, build the appropriate user hierarchy and set
the AttributeHierarchyVisible property to False for the Date attribute
in this instance. You can fully disable attributes that will not be queried but
are still needed, such as for calculations. Set AttributeHierarchyEnabled
to False, AttributeHierarchyOptimizedState to NotOptimized, and
AttributeHierarchyOrdered to False. For attributes that need to be modeled
but are infrequently used, consider setting their AttributeHierarchyVisible
property to False. The will not be visible but can still be referenced via MDX
queries.
■ (^) On large dimensions use the AttributeHierarchyDisplayFolder to group
related attributes and DisplayFolder for user hierarchies.
Best Practice
Well-organized dimensions using well-understood names are essential to gaining acceptance for
interactive applications — most users will be overwhelmed by the amount of available attributes.
Excluding unused attributes not only helps simplify the user’s view of the data, it also can greatly
speed performance — especially for cubes with substantial calculations because the more attributes,
the larger the number of cells each calculation must consider.
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